lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 17 Oct 2022 16:09:46 -0400 From: "Michael S. Tsirkin" <mst@...hat.com> To: Jason Wang <jasowang@...hat.com> Cc: davem@...emloft.net, edumazet@...gle.com, kuba@...nel.org, pabeni@...hat.com, gautam.dawar@...inx.com, virtualization@...ts.linux-foundation.org, netdev@...r.kernel.org, linux-kernel@...r.kernel.org Subject: Re: [PATCH net] virtio-net: add cond_resched() to the command waiting loop On Mon, Sep 05, 2022 at 12:53:41PM +0800, Jason Wang wrote: > Adding cond_resched() to the command waiting loop for a better > co-operation with the scheduler. This allows to give CPU a breath to > run other task(workqueue) instead of busy looping when preemption is > not allowed. > > What's more important. This is a must for some vDPA parent to work > since control virtqueue is emulated via a workqueue for those parents. > > Fixes: bda324fd037a ("vdpasim: control virtqueue support") > Signed-off-by: Jason Wang <jasowang@...hat.com> Acked-by: Michael S. Tsirkin <mst@...hat.com> > --- > drivers/net/virtio_net.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index ece00b84e3a7..169368365d6a 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -2000,8 +2000,10 @@ static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd, > * into the hypervisor, so the request should be handled immediately. > */ > while (!virtqueue_get_buf(vi->cvq, &tmp) && > - !virtqueue_is_broken(vi->cvq)) > + !virtqueue_is_broken(vi->cvq)) { > + cond_resched(); > cpu_relax(); > + } > > return vi->ctrl->status == VIRTIO_NET_OK; > } > -- > 2.25.1
Powered by blists - more mailing lists